Rail vehicle with an air-tight supply duct containing bonded components

ABSTRACT

A rail vehicle includes a raised roof region, a shell or body shell structure, and at least one air-tight supply duct in the raised roof region. The supply duct includes at least one component which is inserted by bonding into the shell or body shell structure.

The present invention relates to a rail vehicle having at least one air-tight supply duct in the raised roof region, characterized in that the supply duct comprises at least one component which is inserted into the rail vehicle shell structure by means of bonding.

PRIOR ART

One possibility of optimizing the energy consumption of rail vehicles, with far-reaching consequences especially for the CO₂ equivalent of a user, is the use of technically constructive means which improve the aerodynamics both of driving units and of rail vehicle carriage bodies. A proven means for reducing the air resistance has been found to be the use of special raised roof profiles which conventionally form a favorable flow profile on the upper outer skin of the rail vehicle and at the same time achieve progress in the reduction of the external noise and sonic boom. Furthermore, these roof constructions may also receive portions of the supply devices. The prior art also includes the use of differently constructed raised roof profiles at predetermined rail vehicle positions, which can be assembled in a modular manner and which in their specific sequence afford the rail vehicle as a whole extraordinarily favorable aerodynamics.

Modern raised roof constructions thus provide not only the possibility of optimized vehicle geometry, but also enable as a result of their construction the use of improved supply devices, which are not known in the prior art. This is particularly important for supply devices which are structurally complex and/or which have to have the highest possible level of reliability. It is further important for the supply devices to be readily accessible for maintenance purposes. Supply devices of the type mentioned include, for example, the air-conditioning modules and in particular here the air-conditioning ducts which are constructed in a pressure-tight and air-tight manner. Conventional air-conditioning ducts which are constructed in accordance with the prior art are inserted securely into the rail vehicle shell frame by means of air duct apertures. In this instance, the air-conditioning ducts are received by components which are integrated in the rail vehicle shell structure by means of conventional thermal joining methods. As a result of dimensional tolerances in the rail vehicle shell and generally as a result of the use of relatively inflexible components, very complex welding operations have to be carried out in order to ensure a gas-tight connection between the shell and the component. The thermal loading often also leads to distortion of the components which can consequently lead to a poor seal between the air-conditioning duct and the component. The method can be carried out only with a high level of complexity and is consequently costly. A subsequent time-intensive sealing verification operation is obligatory for this production method.

The current prior art further involves the components for the duct apertures of the supply ducts being welded into the rail vehicle shell frame with a horizontal orientation. These components have for receiving the supply ducts an opening which is orientated substantially downward, that is to say, toward the inner space of the vehicle. This results in the supply ducts which generally extend in the longitudinal direction relative to the rail vehicle having to be provided with supply duct connections which are constructed in an angled manner. This is technically unfavorable owing to the flow relationships which are produced in the supply duct.

As a result of the use of raised roof regions, it is now possible to produce a perpendicular installation of the supply duct aperture for receiving a supply duct which in the context of the connection guiding and safety has clear advantages and results in considerable savings in terms of installation time and logistics. In particular it is no longer necessary to have angled connections which are constructed in a complex manner and which are unfavorable in technical flow terms. In the case of gaseous media, the optimized geometry results in a reduction of the flow resistance and consequently also the noise development.

An object of the present invention is therefore to provide an additional technical solution for a rail vehicle which overcomes the previous difficulties in the construction and installation of air-tight supply ducts and provides a simple, safer and cost-effective construction for installing an air-tight supply duct.

This object is achieved according to claim 1. Specific embodiments of the invention are set out in the dependent claims.

The invention relates to a rail vehicle having at least one air-tight supply duct in the raised roof region, characterized in that the supply duct comprises at least one component which is inserted into the rail vehicle shell structure by means of bonding. As a result of the bonding of at least one component of the air-tight supply duct to the rail vehicle shell structure, it is possible to produce in a simple manner a resilient and air-tight connection between the component and the shell structure. A thermal loading of the component and the shell structure during the assembly can be dispensed with, which has a positive effect on the accuracy of the shape of the components. In addition, complex verification of the tightness of the connection location can be dispensed with. The bonding additionally enables simple and flexible compensation for production tolerances both of the shell structure and of the component. Rail vehicles in the context of the invention are vehicles which move on tracks comprising rails which are arranged in pairs and/or in parallel (rail line). This category includes, for example, railways, regional rail systems, underground trains, suspension type trains, rail vehicles, goods wagons, passenger carriages, locomotives, railcars and driving units.

Supply ducts constitute compartments within the rail vehicle which are separated by means of walls and which generally extend in the longitudinal axis of the rail vehicle and provide at the inner side thereof media such as air, gas, water or electricity. Supply ducts in the raised roof region of a rail vehicle are located below the outer casing in the upper region of the rail vehicle. These include in particular air-conditioning, water, air, hydraulic, compressed air and electricity supply ducts.

A supply duct in the context of the invention is understood to be air-tight when the unintentional gas exchange between the inner and outer space of the supply duct per hour is less than 1% of the duct inner space. This does not include the exchanged gas proportions which are exchanged for the correct operation of the supply duct.

Suitable components which can be used in the context of the invention for the integration and fixing of supply ducts in the raised roof region of the rail vehicle shell structure are pre-fabricated molded components of metal, plastics material or composite materials of metal and plastics material which have at least one opening for receiving a supply duct and a planar bonding face for connecting to the rail vehicle shell structure. Furthermore, the component may preferably have elements for the secure connection of the supply ducts. These may be constructed in the form of threads, notches, recesses, retention devices, counter-pieces or clamps. The component comprises an opening which is suitable for receiving a supply duct. The symmetrical construction of the component may be varied and is substantially dependent only on the configuration of the supply duct. Both the component and the component opening may, for example, be formed symmetrically (rectangular, square, round, oval, triangular, octagonal) or in an irregular manner.

The connection between the rail vehicle shell structure and the supply duct is carried out according to the invention by means of a component which is bonded to the rail vehicle shell in a resilient, positive-locking and planar manner. Adhesive bonding is intended to be understood to be the planar connection of materials which are the same or different using a mostly foreign substance which bonds to the surfaces of the components to be connected and which transmits the forces from one joining component to the other. This type of fixing has been found to be particularly advantageous since both the mechanical demands on the joining location and the gas sealing can be ensured in a highly reliable and simple manner by means of a bonding method. As a result of the bonding, small and medium tolerances in the component and the rail vehicle shell structure can be compensated for. In the context of the selected joining method, there is according to the invention no distortion of the component or the rail vehicle shell structure since a thermal loading of these locations is prevented. There is a joining location with a uniform distribution of stresses. In the region of the bonding location, no gap corrosion can occur, good damping properties are produced by means of the bonding and a high dynamic strength of the bonded connection is further achieved. This leads to improved crash and rigidity properties in the rail vehicle shell structure.

In another embodiment of the invention, the air-tight supply duct may comprise an air-conditioning duct. An air-conditioning duct is included among air-conditioning technical devices and forms a portion of an installation for ventilating and/or heating and/or cooling and/or filtering the air of a rail vehicle. The supply of air is carried out in this instance either via a forced ventilation, this means by way of mechanically produced air movement, or only by means of ventilation without mechanically produced air movement. The air-conditioning duct has the function of guiding the air, distributing the air and directing the air into the space and optionally guiding it out of the rail vehicle space again. The method according to the invention may be particularly suitable for the installation of air-conditioning ducts since, particularly for air-carrying supply ducts, an active noise-damping by means of resiliently bonded connections may be advantageous.

In another aspect according to the invention, the component may be connected to the rail vehicle shell structure by means of a thick-film adhesive having a thickness greater than or equal to 3 mm and less than or equal to 20 mm. An adhesive in the context of the invention may include either single-component or multi-component adhesives. Single-component adhesives are chemically hardening adhesives such as, for example, epoxy resins, polyurethanes, cyanacrylates, silicones; chemically and physically hardening adhesives, such as, for example, reactive melt adhesives, post-crosslinking dispersion adhesives; physically hardening adhesives, such as, for example, melt adhesives, contact adhesives, solvent adhesives, plastisols; non-hardening adhesives, such as, for example, acrylates, natural and synthetic rubber. Multi-component adhesives may include chemically hardening two-component adhesives, such as, for example, epoxy resins, polyurethanes, methacrylates, silicones. The adhesive preferably has a thickness greater than or equal to 3 mm and less than or equal to 20 mm. This thickness of the adhesive layer has been found to be particularly suitable from the points of view of tolerance compensation of the components, the service-life of the adhesive layer, the damping properties and the air-tightness and can in terms of its properties also comply with the provisions of codes of practice as set out, for example, in the German Welding Society Code of Practice “Resilient thick-film bonding in rail vehicle construction”. Greater adhesive thicknesses are generally not mechanically stable for a sufficiently long period of time.

There may further be provision according to the invention for the thick-film adhesive to comprise an adhesive which is based on polyurethane and which after hardening has a shearing strength greater than or equal to 1.5 N/mm² and less than or equal to 20 N/mm². Particularly preferred are one-component or two-component adhesives which after hardening may have a high level of resilience and a high shearing strength. The range of shearing strength set out above may enable a reliable, materially engaging connection between the components, which is additionally sufficiently resilient to withstand the vibrations which occur during operation of the rail vehicle. The measurement of the shearing strength of the connection may be carried out in accordance with methods known to the person skilled in the art. A possibility for determining the shearing strength may be produced in accordance with DIN EN 1373. Possible one-component or two-component polyurethane systems may, for example, be selected from Sikaflex252, Sikaflex552 and the booster system SikaForce7550 LO5 VP from the company Sika.

The rail vehicle according to the invention may in a specific embodiment contain a supply duct having a component which is selected from the group of light metal cast components or composite fiber plastics materials. In relation particularly to the weight saving, components of light metal or composite fiber plastics materials may be suitable in a particularly advantageous manner in the context of the invention. The term light metals is in this instance generally used to refer to metals and alloys whose density is less than 5 g/cm³. Light metals include lithium, sodium, potassium, rubidium, cesium, francium, beryllium, magnesium, calcium, strontium, barium, scandium, yttrium, titanium and aluminum. In a particularly preferred manner, aluminum and magnesium can be used as a material for a light-metal joining component. It is further preferable for the molded components to be produced by means of a casting process. Cast molded components may be particularly durable as a result of their mechanical strength and torsion-resistance. In another aspect according to the invention, the component may comprise an aluminum cast component. The cast component can in this instance be produced in an appropriate manner either by means of chill casting or sand casting. Aluminum has been found to be particularly suitable as a material for producing cast components for installation in a rail vehicle supply duct as a result of its high level of strength and torsion resistance, its low density and its corrosion and weather resistance.

In another aspect of the invention, the component comprises an opening which is orientated substantially orthogonally relative to the rail vehicle longitudinal axis. Advantageously, the opening of the component is constructed in such a manner that a subsequent installation of a supply duct through the opening can be carried out without redirection in the direction of the vehicle longitudinal axis. An orientation of the opening so as to be orthogonal with respect to the rail vehicle longitudinal axis means that the surface vector of the opening is orientated substantially parallel with the rail vehicle longitudinal axis. As a consequence of the production tolerances of the component and rail vehicle shell structure, the term orthogonal is substantially intended to be understood to mean that discrepancies between the two vectors of the order of magnitude of less than or equal to 20° may be produced. Contrary to the previous prior art, it has been found that the installation of the component with an orthogonal orientation of the opening may lead to an improved through-flow of the supply duct with a smaller resistance. This may have an advantageous effect on the noise emissions of the supply duct. Complex angular components for connecting individual supply ducts may be dispensed with according to the invention.

In another aspect of the invention, the component may provide spacer elements which enable a defined spacing between the component and the rail vehicle shell structure surface. Spacer elements are intended to be understood to be protuberances, pins, webs, washers or spacer disks which are fitted to the component and which provide for the bonding process a constant spacing of the component with respect to the rail vehicle shell structure. Preferably, the spacer elements in the context of the production of the component may be produced from the same cast material and be produced in the same production step as the component itself. In other embodiments, however, these spacer elements may also be fitted separately to the component or the rail vehicle shell structure prior to bonding. The spatial expansion of the spacer elements can be selected as a function of the desired adhesive thicknesses, and may advantageously be between 3 and 20 mm. Preferably, the relationship of the surface area of the spacer elements with respect to the surface area of the entire adhesive face may be from a value greater than or equal to 1:100 to a value smaller than or equal to 20:100.

In another embodiment, the spacer elements may be provided for receiving connection elements. The receiving of connection elements in the spacer elements of the component structure may in addition to bonding contribute to further mechanical securing of the component to the rail vehicle shell structure. The connection elements may in the context of the component installation be inserted into the prepared spacer elements and may have a length which is suitable for enabling an additional bilateral securing of the component to the rail vehicle shell structure. The connection elements may in this instance be constructed so as to be both releasable, for example by means of screws or pins, or non-releasable by means of rivets or weld locations. Preferably, these additional elements can be used in vehicle regions with high mechanical loads in order to ensure an additional connection of the component to the rail vehicle shell structure.

Furthermore, a method for producing a rail vehicle is in accordance with the invention, wherein the rail vehicle comprises at least one air-tight supply duct in the raised roof region having a component according to the invention.

The above-described properties, features and advantages of this invention and the method by which they are achieved will become clearer and easier to understand in conjunction with the following description of the drawings, in which in particular:

FIG. 1 is a schematic illustration of a thick-film bonded cast frame within a rail vehicle shell structure;

FIG. 2 is a schematic cross section of the fitting of a component into a rail vehicle shell structure.

FIG. 1 is a schematic illustration of a raised roof region of a rail vehicle. The component (110) for receiving an air-tight supply duct (not illustrated in the drawings) is bonded to the rail vehicle shell structure (100) at the edge regions thereof. The component (110) for receiving an air-tight supply duct is further provided with spacer elements (120). The opening (130) of the component (110) is in this instance constructed in a rectangular manner and can receive a supply duct. The opening (130) in the component (110) is orientated substantially orthogonally with respect to the rail vehicle longitudinal axis; this means that the surface vector of the opening is orientated substantially parallel with the rail vehicle longitudinal axis.

FIG. 2 is a schematic cross section of the fitting of the component (110) into the shell region (100). The component (110) is connected to the rail vehicle shell structure by means of the circumferential adhesive layer (140). The spacer elements are located within the adhesive layer and are not illustrated.

Although the invention has been illustrated more specifically in detail and described by the preferred embodiment, the invention is not limited by the disclosed examples and other variations may be derived by the person skilled in the art without departing from the scope of protection of the invention. 

1-10. (canceled)
 11. A rail vehicle, comprising: a raised roof region; a rail vehicle shell structure; and at least one air-tight supply duct disposed in said raised roof region, said at least one air-tight supply duct having at least one component inserted into said rail vehicle shell structure by bonding.
 12. The rail vehicle according to claim 11, wherein said at least one air-tight supply duct includes an air-conditioning duct.
 13. The rail vehicle according to claim 11, wherein said at least one component is connected to said rail vehicle shell structure by a thick-film adhesive having a thickness greater than or equal to 3 mm and less than or equal to 20 mm.
 14. The rail vehicle according to claim 13, wherein said thick-film adhesive is an adhesive based on polyurethane having a shearing strength greater than or equal to 1.5 N/mm² and less than or equal to 20 N/mm² after hardening.
 15. The rail vehicle according to claim 11, wherein said at least one component is selected from light metal cast components or composite fiber plastics materials.
 16. The rail vehicle according to claim 11, wherein said at least one component is an aluminum cast component.
 17. The rail vehicle according to claim 11, wherein said at least one component has an opening formed therein being oriented substantially orthogonally relative to a longitudinal axis of the rail vehicle.
 18. The rail vehicle according to claim 11, wherein said at least one component has spacer elements forming a defined spacing between said at least one component and a surface of said rail vehicle shell structure.
 19. The rail vehicle according to claim 18, wherein said spacer elements are configured to receive connection elements.
 20. A method for producing a rail vehicle, the method comprising the following steps: providing a raised roof region and a rail vehicle shell structure; providing at least one air-tight supply duct in the raised roof region; and inserting at least one component of the at least one air-tight supply duct into the rail vehicle shell structure by bonding. 